1. Field of the Invention
This invention relates to valves, and more particularly to an improved diverter valve for providing fluid communication between a main port and a first and a second secondary port.
2. Background of the Invention
Diverter valves have the common characteristic of diverting fluid flow from a main port to either a first secondary port or a second secondary port. The main port can either be an input port or an output port with the first and second ports being either an output port or an input port, respectively. The primary function of the diverter valve is to allow fluid communication between the main port and only one of the first and second ports. In general, diverter valves prevent communication between the first and second ports.
Many diverter valves are commonly referred to as Y valves since these diverter valves take a basic Y-shape. The main port is the linear portion of the Y-shape and first and second ports are the divergent or the V-shape portion of the Y-shape. The Y valve has become very popular since the Y valve enables the diversion of fluid between a main port and either the first and second ports while maintaining excellent flow characteristics. The excellent flow characteristics of the Y valve are due to the fact the fluid is not substantially redirected into another direction such as a change in direction of ninety degrees or greater. The Y valve merely redirect the fluid flow through an acute angle such as a change in direction of much less than ninety degrees.
In general, diverter valves were formed from a valve housing having an internal valve chamber. The main port and the first and second ports communicated with the internal valve chamber. A valve element was movable within the internal valve chamber. The valve element was movable between a first and a second position for respectively communicating the main port to either the first port or the second port. The valve element could be slidably movable within the internal valve chamber or may be rotatably moveable within the internal valve chamber depending upon the design of the diverter valve.
U.S. Pat. No. 2,485,504 to Morgan discloses a valve comprising a body provided with a cylindrical bore having a circumferential groove therein and two ports communicating with the bore at opposite sides of the groove. A valve piston is mounted in the bore to control the flow of fluid between the ports and having a cylindrical portion which fits the bore closely. The piston and body are relatively slidable in the direction of the axis of the bore. A ring of yieldable material is mounted in the groove having an unstressed inside diameter somewhat less than the diameter of the bore so that the cylindrical portion of the piston may stress the ring to prevent leakage of fluid past the same. The piston also has a portion of reduced diameter connected to the cylindrical portion by a gradually tapered surface. The diameter of the reduced portion is substantially equal to the inside diameter of the unstressed ring. The reduced portion has one or more longitudinally extending grooves therein to permit fluid flow between the ports when the piston and body are so positioned relatively as to bring the reduced portion within the ring.
U.S. Pat. No. 2,524,142 to Seeloff discloses a fluid valve comprising a body member having a bore therein with a core member being slidably received in the bore. The improvement consists of an annular recess in one of the members and an annular valving land on the one of the members adjacent the recess and separated therefrom by an annular rounded shoulder. A circumferential groove in the other of the members is located to overlie the recess when the core member is in one axial position and to overlie the annular land when the core member is in its other axial position during normal operation of the valve. The other member is loosely interfitted with respect to the one of the members in the region of the annular land, and a toroidal-shaped fluid impervious ring of resilient and deformable material positioned in the groove. The groove has greater axial length than the thickness of the ring whereby the ring may have limited rolling contact with the rounded shoulder. An annular recess in the other member adjacent to the groove coacts with the first mentioned annular recess to provide an axial fluid passage upon the core member being moved to cause the groove and ring to overlie the first mentioned passage.
U.S. Pat. No. 2,782,801 to Ludwig discloses a valve structure comprising a valve housing having a bore formed therethrough communicating with inlet and outlet ports with a valve spool body being slidable in the bore. A plurality of stepped peripherally disposed cylindrical flanges are formed on the body intermediate the ends. The flanges are spaced apart by channels of equal width and which extend inwardly beyond the surface of the spool body. A body of flexible sealing material is molded on the stepped flanges and filling the channels and engaging a face of the largest of the stepped flanges and projecting beyond the periphery of the largest flange and engaging the inner surface of the bore. The outer surface of the sealing body is tapered away from the periphery thereof to the periphery of the spool body.
U.S. Pat. No. 3,990,477 to Johnson discloses a flow control valve including a valve body defining a main bore and a cross-drilled bore communicating therewith. A valve spool is reciprocable within the main bore and includes first and second lands connected by a reduced diameter connecting portion. The connecting portion has fixed relative thereto and thereabout an annular rib positioned between the two lands. The rib acts as a guide to direct fluid substantially perpendicular to the axis of reciprocal motion of the spool when the spool is positioned to allow fluid flow between the main and cross-drilled bores to minimize fluid flow forces tending to hold the spool in an open position.
U.S. Pat. No. 4,066,239 to Hall discloses a fluid control valve including a valve body having a pump inlet port for connection to a relatively high pressure pump and a drain outlet port for connection to a substantially atmospheric pressure reservoir. A valve spool has a metering slot leading from the peripheral surface of a first land to a peripheral surface of a second land. The metering slot includes a substantially cylindrical pocket recessed into the second land. A groove is formed in the first land and a reduced diameter portion is positioned between the lands. The groove connects the peripheral surface of the first land with the cylindrical pocket and has an arcuate surface portion leading from the peripheral surface of the first land. An elongated bottom surface is positioned substantially parallel to the longitudinal axis of the spool and tangent to the arcuate surface portion. The spool is movable along a longitudinal axis between a first position at which flow from the pump inlet port to the drain outlet port is metered outwardly relative to the spool through the cylindrical pocket and a second position at which fluid flow from the pump inlet port to the drain outlet port is metered inwardly through the groove. The metering slot is of a construction sufficient for directing the fluid metered inwardly through the groove into the cylindrical pocket to generate a force acting on the spool tending to close the metering slot.
U.S. Pat. No. 4,182,375 to Fukano et al. discloses a spool-sleeve type change-over valve. The axial width of the intake passage is reduced relative to that of the discharge passage within a range in which the same cylinder response as attained by intake and discharge passages of the same axial width is retained.
U.S. Pat. No. 4,739,797 to Scheffel discloses a hydraulic piston-valve-type control valve that includes a housing in which a control piston is longitudinally displaceably disposed. The control piston regulates at least one fluid stream that flows through the housing by means of annular recesses and hence control surfaces formed on piston collars about a piston core. This regulation is effected by coupling the recesses between the piston collars, while appropriately longitudinally shifting the control piston, with annular control chambers on the housing side. The collars of the control piston are provided with control edges that progressively release the control chambers. The problem with heretofore known valves was that an undesired sudden increase in the flow forces could not be avoided. In addition, the manufacture of the corresponding configurations of the control edges was complicated and expensive. To remedy this problem, the course of the control edges that release or close the control chambers on the housing side, when viewed in the circumferential direction of the control piston, has no segment that extends linearly and at right angles to the center line of the piston. Each control edge follows a symmetrical course relative to a central cross section taken through its circumferential development, and each control edge also at least twice provides for the full cross-sectional opening area of the control piston.
U.S. Pat. No. 4,899,842 to Emori et al. discloses a steering force controller for power steering apparatus which controls an oil pressure supplied to an oil pressure reaction chamber in accordance with a position of a spool valve which is caused to be displaced fore and aft in accordance with a vehicle speed. The spool valve is slidably fitted into a sleeve which is in turn disposed within a bore formed in a housing. The oil pressure supplied to the oil pressure reaction chamber can be controlled in accordance with the displaced position of the spool valve with respect to the sleeve. A regulating member is provided for causing an axial displacement of the sleeve, thus facilitating a regulation of a relative position between the spool valve and the sleeve.
U.S. Pat. No. 5,058,626 to Takaoka et al. discloses a hydraulic pressure control valve including a valve body having a slide bore with a circular cross-section and an inlet port opened in an inner surface of the slide bore. A control pressure port and an outlet port are disposed at axially spaced-apart distances in this sequence. A valve spool axially is slidably fitted in the valve body with and a first variable orifice and a second variable orifice being formed between the valve body and the valve spool. The first variable orifice controls the degree of communication between the inlet port and the control pressure port. The second variable orifice controls the degree of communication between the control pressure port and the outlet port. In this hydraulic pressure control valve, the valve spool has smaller diameter portions coaxially formed therein to define annular oil passages between the inner surface of the slide bore and the valve spool and each smaller diameter portion has an outer diameter set uniformly over the axially entire length thereof.
U.S. Pat. No. 5,297,777 to Yie discloses a flow control valve for instant on-off operations with gases or liquids at relatively high pressures, such as pressures between 10,000 psi and 100,000 psi. The valve includes a valve body having two or more valve cavities in communication with each other and defined by two end seal assemblies and one or more valve port seal assemblies. An elongated, round, sliding valve stem is centrally located through the seal assemblies. End plugs are used to support the end seal assemblies. The valve stem has fluid passages which are preferably machined at a mid-section of the valve stem. The valve stem is slid parallel to a longitudinal axis to allow or prevent communication between the valve cavities by way of the fluid passage of the valve stem. Two opposite ends of the valve stem are either not exposed to the working fluid or are exposed to different pressures of the working fluid. With both opposite ends of the valve stem not being exposed to the working fluid, fluid-induced forces of relatively high magnitude are not exerted on the valve stem.
U.S. Pat. No. 5,551,482 to Dixon et. al. discloses a direct drive servo-valve having a molded plastic housing. A metal sleeve having a spool valve slidably disposed therein is placed within opposed cavities formed within opposite housing halves. The housing halves are brought together under pressure and an ultrasonic horn is activated. Energy directing beads formed on the housing halves as well as interfering surfaces about the periphery melt under a pressure and ultrasonic energy allowing the two housing halves to move toward each other and mate. Upon deactivation of the ultrasonic horn, the molten plastic material cools and forms a seal about flow ports in the metallic sleeve as well as a fusion bond about the periphery of the housing.
U.S. Pat. No. 5,606,901 to Oki discloses a turning-purpose hydraulic circuit characterized in that a discharge passage of a hydraulic pump is connected to a variable relief valve and a pump port of a directional switching valve. A first actuator port and a second actuator port of the directional switching valve are connected to a turning-purpose hydraulic motor. The pilot pressure of a pilot valve is introduced into pressure chambers for controlling a spool in the directional switching valve and is also introduced into a pressure chamber for controlling a set pressure in the variable relief valve. A metering input side portion along which a pressurized oil flows from the pump port of the spool to the first or second actuator port is formed with a portion having a configuration such that a flow force may not be produced thereat. A metering output side portion along which the pressurized oil flows from the first or second actuator port of the spool to a tank port is formed with a portion having a configuration such that a slow force may be produced thereat.
One unique diverter valve developed by the prior art was the spool diverter valve. The spool diverter valve incorporated a valve element in the general shape of a spool. The spool valve element was slidable within the internal valve chamber between a first and a second position for diverting fluid between the main port and either the first or the second port. This unique spool diverter valve was used for diverting highly viscous fluids operating at high temperatures and high pressures. In many cases, these spool diverter valves were used in association with polymer filters for filtering synthetic fibers, films, resins and the like.
The spool valve element and the internal valve chamber had a unique configuration for eliminating all regions within the spool diverter valve where the viscous fluid could remain stagnant or remain in an eddy. The spool valve element in combination with the internal valve chamber insured the viscous fluid was constantly moving through the spool diverter valve and all incoming viscous fluid was replacing the viscous fluid within the internal valve chamber. This is commonly referred to as the residence time of a fluid component. The spool diverter valve ensured that no viscous fluid would remain within the internal valve chamber during the operation thereof.
The spool diverter valve of the prior art met with substantial success and satisfied many of the needs for diverter valves for use with viscous fluids operating at high temperatures and high pressures. One disadvantage of the aforementioned spool valve diverter valve was the physical configuration of the main port relative to the first and second ports. The first and second ports were configured into a V-shape configuration with the main port positioned between the first and second ports. The spool valve element did not permit the main port to be located in a Y-shape configuration as some of the other diverter valves of the prior art. Accordingly, the viscous fluid had to change in direction almost 180 degrees when passing between the main port and either the first or the second port.
Therefore it is an object of the present invention to provide an improved diverter valve which is suitable for use with viscous fluids operating at high or low temperatures and high pressures that may be fashioned in a Y-shape configuration.
Another object of this invention is to provide the improved diverter valve having a valve element and the valve chamber configured to prevent viscous fluids from being entrapped within regions of the valve chamber.
Another object of this invention is to provide the improved diverter valve having a lower residence time within the diverter valve over similar purpose diverter valves of the prior art.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.
The present invention is defined by the appended claims with specific embodiments being shown in the attached drawings. For the purpose of summarizing the invention, the invention relates to an improved diverter valve comprising a valve housing defining an internal chamber. A main port communicates with the internal chamber of the valve housing. A first and a second port communicate with the internal chamber of the valve housing. The main port communicates with the first and second ports in a Y-shape configuration. A spool valve element is slidably disposed in the internal chamber. An actuator slides the spool valve element from a first position whereat the main port is in fluid communication with the first port to a second position whereat the main port is in fluid communication with the second port for diverting fluid between the main port and the first port and the main port and the second port.
In a more specific embodiment of the invention, the internal chamber of the valve housing is a substantially cylindrical internal chamber. The cylindrical internal chamber extends between a first cylindrical end and a second cylindrical end. The main port communicates with the internal chamber of the valve housing through a cylindrical sidewall thereof. A first and a second port communicate with the internal chamber of the valve housing through a cylindrical sidewall thereof. The main port communicates with the cylindrical sidewall of the internal chamber on a side of the internal chamber opposite to the first and second port communicating with the cylindrical sidewall of the valve housing.
The spool valve element is slidable within the cylindrical internal chamber from the first position adjacent the first cylindrical end to the second position adjacent the second cylindrical end. The actuator includes a threaded actuator drive for sliding the spool valve element from the first position to the second position. The threaded actuator drive comprises a rotatable bushing threadably engaged with threaded stem for linearly moving the threaded stem upon rotation with the rotatable bushing. The threaded stem is connected for sliding the spool valve element from the first position to the second position upon rotation with the rotatable bushing.
The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.